title: Cell-free biosynthesis of erythroglycan in a microsomal fraction from K-562 cells.
abstract: Particulate membrane preparations from K-562 [human CML (chronic-myelogenous-leukaemia)-derived] cells catalyse the transfer of [3H]galactose from UDP-[3H]-galactose and [3H]N-acetylglucosamine from UDP-[3H]N-acetylglucosamine into an endogenous product that on digestion with Pronase yields long-chain glycopeptides (mol.wt. 7000--10 000) called 'erythroglycan'. Incorporation of either labelled sugar increased up to 60 min of incubation time. The labelled erythroglycan was isolated by chromatography on Sephadex G-50 and characterized by digestion with endo-beta-galactosidase from Escherichia freundii, followed by analysis on Bio-Gel P-2 and paper chromatography. This digestion gave the following four products: (1) a disaccharide with the sequence beta GlcNAc-beta Gal; (2) a trisaccharide with the sequence betaGal-betaGlcNAc-beta Gal; (3) a larger oligosaccharide containing galactose and N-acetylglucosamine; and (4) a putative protein-linkage region.
mesh_terms: D000117:Acetylglucosamine / Q000378:metabolism; D001457:Anion Exchange Protein 1, Erythrocyte; D002460:Cell Line; D002474:Cell-Free System; D002854:Chromatography, Paper; D005690:Galactose / Q000378:metabolism; D006026:Glycoside Hydrolases; D006801:Humans; D007425:Intracellular Membranes / Q000378:metabolism; D007951:Leukemia, Myeloid / Q000378:metabolism; D008565:Membrane Proteins / Q000096:biosynthesis*; D008861:Microsomes / Q000378:metabolism*; D001616:beta-Galactosidase
chemical_list: D001457:Anion Exchange Protein 1, Erythrocyte; D008565:Membrane Proteins; C018059:erythroglycan; D006026:Glycoside Hydrolases; C026093:keratan-sulfate endo-1,4-beta-galactosidase; D001616:beta-Galactosidase; D000117:Acetylglucosamine; D005690:Galactose